Unleashing the Science - BIL funding supports BLM California’s rare plant and pollinator project at the Pine Hill Preserve

Unleashing the Science - BIL funding supports BLM California's rare plant and pollinator project at the Pine Hill Preserve

Jul 25, 2024

Story by Philip Oviatt, Public Affairs Officer, BLM California - Central California District. Photos provided by Landon Eldredge, BLM. Header Photo by Jesse Pluim, BLM.

Investments from President Biden's Investing in America agenda and the Bipartisan Infrastructure Law (BIL) support BLM California's pollinator project to collect and study native bees, butterflies, and moths on the Pine Hill Preserve in California.

This project improves BLM's understanding of the pollinator network by identifying the associations between plants and potential pollinating insects. Results of this project will improve management of rare plants and other native plants that share pollinators in the area.

Bombus vosnesenskii on PhaceliaDiadasia bituberculata on Calystegia stebbinsii

The Pine Hill Preserve is a cooperative conservation effort among 10 federal, state, and local entities to protect the habitat of eight rare plant species and the Preserve's unique resources. The Preserve lands and the adjacent Kanaka Valley are located approximately 30 miles east of Sacramento, California and consist of 4,940 acres of unique habitat on gabbro soils of the Rescue series.

BIL sign at Pine Hill Preserve

"Through this project we are gaining insight into the unique relationships between pollinators and our rare plants," said BLM Biological Technician Landon Eldredge. "So far, we have documented more than 150 species of bees from 70 different plants and 21 species of butterflies and moths. This information shows us where pollinator resources are shared, and which bees, butterflies, and moths may be partial to specific plant species."

Eldredge added: "We were thrilled to discover new populations of two species of milkweeds through this project. In May 2024, we documented the first monarch caterpillars on Preserve-managed lands."

Landon Eldredge stands next to a poster about pollinators at Pine Hill Preserve.Narrowleaf milkweed

The BLM has partnered with expert taxonomists from UC Davis and Utah State University to identify and expand research efforts on native bees. Data will be used to inform management decisions that will further the conservation of rare plants. Through the use of careful hand netting techniques, researchers can focus on the unique relationships that exist between pollinators and rare plant species at the Preserve.

Duplicate specimens from this project are housed at the UC Davis Bohart Museum of Entomology and at the U.S. Department of Agriculture's Logan Bee Lab at Utah State University. This collaboration makes the specimens more accessible to scientific researchers without impacting the rare plants and animals of the Pine Hill Preserve.

Additionally, BIL funds have furthered the BLM's ability to manage natural habitat for rare plant species. The unique gabbro soils which are found on the Preserve sustain about ten percent of California's native flora. Four of the eight rare plant species that grow at the Preserve are endemic to western El Dorado County, California, which means they grow nowhere else in the world.¹

This assemblage of rare plants is part of a unique botanical community confined to soils known as the Rescue soils, named after the nearby community of Rescue, California. These unique plant species, five of which have federal protections, are all included in the California Native Plant Society's rare plant ranking system and are protected at the Preserve.

"Implementation of different management practices, including invasive species management, is ongoing and helps us conserve and recover rare plant species present in these unique habitats," said Eldredge. "This helps us protect the functionality of ecosystems and associated biological diversity."

The mission of the Pine Hill Preserve is to conserve in perpetuity the rare plant species and plant communities of western El Dorado County. To view the activities happening at the Preserve, check out the Preserve's website.

BLM California is grateful for the BIL funds that support pollinator and habitat management efforts at the Pine Hill Preserve. BIL funds also help sustain and expand ecosystem restoration initiatives across the state of California, improving the health of the habitats that the BLM manages.

Footnote:

1- The California Native Plant Society (CNPS) considers El Dorado mule-ears (Wyethia reticulata), a perennial herb, and Red Hills soaproot (Chlorogalum grandiflorum), a flowering plant, to be rare. CNPS lists Bisbee Peak rush-rose (Crocanthemum suffrutescens), a native shrub, as a species that needs to be researched further before an appropriate status can be assigned. Five plant species were listed as endangered or threatened in 1996 by the federal government; these are the only federally listed plant species in El Dorado County, California. Stebbins' morning-glory (Calystegia stebbinsii), Pine Hill ceanothus (Ceanothus roderickii), Pine Hill flannelbush (Fremontodendron decumbens), and El Dorado bedstraw (Galium californicum ssp. sierrae) were listed as endangered. One plant was listed as threatened, Layne's butterweed (Packera (formerly Senecio) layneae).

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This story is part of the "Unleashing the Science" series, showcasing how bureaus within the Department of the Interior produce and apply science to ensure responsible management decisions for our planet now and for the future.

Philip Oviatt